Touch Confetti

1/// Drives a confetti overlay. Keep one in `@State`, attach it with2/// `.touchConfetti(_:)`, then call `burst(at:)` or `fireCannons()`.3///4/// Pieces are pure physics functions of time (gravity + air drag + sway),5/// so a single `Canvas` renders hundreds of them without per-frame state.6@MainActor7@Observable8public final class TouchConfettiEmitter {9    public var palette: [Color]10    /// Downward acceleration, points/s².11    public var gravity: CGFloat12    /// Upper bound on live pieces.13    public var maxPieces: Int14​15    fileprivate private(set) var pieces: [TouchConfettiPiece] = []16    /// Global frame of the overlay, used to aim the cannons.17    @ObservationIgnored fileprivate var bounds: CGRect = .zero18    fileprivate private(set) var burstCount = 019    fileprivate private(set) var cannonCount = 020    private var cleanup: Task<Void, Never>?21​22// ... (click "Show full code" to see more)